Some questions relatng siyah.

[jak]

. I think Novotny?s reconstruction of the Subeixi- bow is an "over-interpretation".


Hi redhawk I have a Novotny subeixi bow and I use it on horseback archery (see my blog if you want: http://jakpradere.blogspot.com/
so I am interessed when you said "over-interpretation" you just "think" or you have any proof to that?what proof please?

best jak

[Adam Karpowicz]

Patrick's idea about the heavy weight crossbow prods is a possibility, given the all-wood-thick-limbed bows of low draw length excavated from the graves.

The bows do not resemble however the grip-deflexed bows I used to make. In my bows, the entire limb, including the outer reflexed part, had to bend, otherwise the wood would not take the stresses of full draw.

In the Scythian bow I am trying to replicate now, the apex of the deflex in the limbs acts almost like a hinge, taking all the bending, somewhat assisted by the grip which also bends to some degree, The outer, reflexed limbs (past the deflex) do not bend at all. It is possible the "cam-effect" of the rigid-ended recurve is present, but I could not determine this yet.

I now belive this bows were not really "engineered" later bows, where the mechanics were better understood. These bows were made to follow the curvature of the ibex horns and forced to deflex in the limbs to be useable. It is possible the extreme deflex in some of them was acquired by keeping them strung and used for a long time, but some of it had to be forced during manufacture.

Adam

[redhawk]

For to be able to discuss everything posted here I need to know, what is a crossbow prod, I can?t find any sense- making translation.

Adam, I don?t believe that the typical Scythian curvature was done for to match the shape of the ibex- horn. The Scythian all wood laminated bows were done in the same curvature. I?m convinced that the design is according the Scythian sense for design or beauty( as Jack has called it).
The reflex does not bend, the grip a little, that?s my experience too.
I state that the key for to understand the Scythian design is the asymmetrical design, I?ll post the details next week within a topic focused on asymmetry in bow- design.

Jak, I know your bow done by L.Novotny, I?m anyway sure it is a great shooter, but I would be more careful calling it a Scythian bow, maybe to call it Novotny?s interpretation of a Scythian bow would be more correct.

Every Scythian bow- finding I?ve examined does not have such a great reflex, this is not a final proof, cause a reflex could have been damaged by time, but not such a sharp reflex as Novotny has done. The final proof is the pic in the book of Toelle- Kastenbein, this Scythian bow looks very similiar to the Subeixi bow you could find posted in the ATARN. Maybe Stephen knows some other pics of unstrung Scythian bows.

Michael

[Patrick Menzies]

Adam , I am still a bit unclear as to why a laminated wooden reflexed limb extending off a deflexed section(either right in the center of the riser as in your Deflex or deflexed inner limb like the Scythian) should not be able to take a reasonable amount of bend. Theoretically a bow with sharp enough deflex will have the outer limb section that uncurls barely moving past being straightened. The energy would be stored in the process of being straightened (like a working recurve) rather than actual bending.
How will that overstress the wood necessarily?
Particularly if is heavy in draw weight and of short draw. Your bows were still drawn normally. What about a thicker limb only drawn 20-22 inches?

I might add that I am thinking only of the early wooden models of Scythian bow. Could it be that the later models were of the same shape in composite structure and the realization came about that there was a better shape for composite construction?

Michael, A crossbow "prod" is merely another word for the bow section of a crossbow. My thinking is that a Scythian bow would be much like the bow you see on some modern crossbows. Usually that would be a very short solid fibreglass recurve of very high draw weight and low draw length. You could remove one of these from the stock and shoot it by hand quite effectively with some practice.

[Adam Karpowicz]

Patrick

I was not clear about the stresses. If, as you say, the outer, past-deflex limb was rigid (as in Subexi bow) the stress of bending is concentrated at the area at and around the end of deflex/beginning of reflex. In a horn/sinew composite the composite limb can take the stress (very high at the small and thick section of bow), while an all-wood bow the stress is too much and the bow would break. This is why the outer limb in an all-wood bow has to bend to reduce this localized stress. Straightening and bending is the same thing. If a bow was much longer, with the area longer as well, then the wood could survive. I calculated the stresses in this type of bow and even in the short western Scythian bow the stress is too much for this short bows.

Michael:

Beauty comes from nature too. The shape of limbs in this bows follow exactly the shape of ibex horn and are build with the inner vertical strip of horn in this shape as well - obviously cut from the sides of ibex horn. I do not see any other explanation why this shape was chosen for the bows. It is quite possible, once the design took hold, bows were made from wood or horn laminations later to imitate it.

Adam

[redhawk]

Maybe I?ve to less fantasy, I guess ibex horns look like other horns used to look.
Due to my knowledge it is proven that the original Scythian hornbow is done with a "puzzle" of hornslats on its belly( this is what Stephen mentioned too in another thread).
I think it was Homer who mentioned that the Scythians have used ibex horns, and till nowadays ibex are living in the Altai- region, so ibex is a sense- making choice.

Michael

[Patrick Menzies]

Adam, I actually meant that the bow would possibly bend between the end of the deflex up to the base of the recurve(with possible slight flex in the recurve as well. That is not to say that I don't think it might also flex slightly through the handle and deflexed areas as well.
I just don't think it would make sense to build a bad hinge into a bow and then work it even more by drawing the bow.
I'm not sure that I would agree that straightening is exactly the same as bending as far as the ability of wood to take the compressive forces.
If you make a forced reflex laminated limb in Perry reflex style it tends to hold reflex better. It also would not chrysal until bent close to the limit of the wood strength.
My idea is to make a handle and deflex inner limb section and splice in two short laminated reflexed limb sections with the typical small recurves. Just to see what the effect of having short "outboard" reflexed limbs seems to be.

[Bede]

To Redhawk, I agree that there is problem in the nomenclature especially when the bow has such a complex profile. Perhaps the Scythian bow can be called a (starting from the "handle") reflex deflex recurve.

Without several alternate versions of this bow to test with shooting, we will not know how much the design affects shooting. Undoubtedly, the smaller, Western Scythian bows shooting short arrows had issues with effective draw length. If they came first, then the later larger bows in the East might be seen to have inherited a less than effective design. Cultural conservatism would then be the reason for the shape rather than aesthetics. I am still not sure why a shorter angular bow was not constructed to shoot the 55 cm Western Scythian arrows. My guess is that the Scythian bow had a background in the area or the area that the Scythians developed parts of their culture.

To Adam, did the bows with exceptionally thick grips have symmetrical limbs? If they didn't, it would be hard to see them as cross bow lathes. Also, I am interested why you consider the recurves to be static rather than working. They have been thinned down and flattened in comparison with the rest of the limbs. I thought this might be it enable bending.

[Patrick Menzies]

Bede, I should be clear that I didn't think of them as actual bows for crossbows but merely functioning in a similar manner. A short, high weight short draw bow designed to shoot a shorter than typical arrow over long range..

[Adam Karpowicz]

To clarify, I include a picture of the bow as it was made. Note where it bends. The outer limbs do not bend - they are still too thick, despite the flattening towards the ends. I should say I made the bow exactly according to the measurements by Stephen - length, thickness and width all along the limbs.

The recurves are therefore static, they do not uncurl. The string lifts-off the limbs as the draw progresses for the increased energy storage in the bow (I have not gone that far though with my tests). Note the bending is concentrated at the deflexed sections, so wood alone (Perry reflexed lams or not) would not take the stress of full draw.

Adam

[Patrick Menzies]

Adam, I am more interested in the possibility of early Scythian bows being laminated wood. If they were then there may be some subtleties of bend being overlooked while the later composite styles are studied.

I can't really see the bows being as reflexed as the one you show. There is the possibility that a good deal of that will disappear with use. But based on the numerous depictions in art of unstrung Scythian bows it would need to be a considerable amount.
Do you think the wooden models found were actually functional?
BTW Nice bow you have made. I'll be following the progress and reports closely.

[Adam Karpowicz]

I forced more deflex before stringing (almost all reflex was gone). This picture shows the work in progress.

I doubt if the wooden bows were functional, unless sinew was added to the backs.

Adam

[Patrick Menzies]

I could see that if you go by the thick three slat bow often mentioned but Michael shows on his site the bow from the Altai being multiple strips with the sidewalls as well and horn only at the recurve bases. No evidence of sinew backing and yet signs of wrapping at the high stress points.
He managed to get a light model working so it remains debatable at this point.

[jack farrell]

A sinewed all horn bow can take a very extreme draw.

One of Tut's bows appears to have been made of vertical laminates, with sinew in between! -j-

[Bede]

Thanks Patrick, I clearly misunderstood.

I think Jack's comment about the Tutankhamun bows should be looked at. They were not highly reflexed, but the David Betteridge-made one I shot which was extremely smooth in drawing and shooting despite the deep cross sections of the limbs.

The vertical laminated bow that Jack mentions appears to have alternating horn and wood laminations across its width that first reminded me of old German composite cross bows though they are even more bizarre in their construction sometimes. The later publication of Xinjiang bows with 3 to 5 laminations in the core seemed quite close in design if not in construction.

I must admit that if I were Adam, I would have approached the bow the way he did, but the more I see the evidence in the form of both artefacts and artistic depictions the less sure I am of how these bows were set up in manufacture.

If we make the assumption that the bows were first small and later were developed into the larger Xinjiang bows, there is not to much equipment needed for a tribesman working on the construction. Unlike us, they would not have heavy forms or other tackle. The bow in construction would probably been put in a box or a bag and carried around in a cart until it was finished.

Whether the first prototypes were sinew, wood and horn composites or laminated wood would not much matter if the reflex was low and the draw was in proportion to the length. We are almost programmed to see the setback handle as a product of the reflex of the bow. This is what is common from modern (the last millennium) bow making. However, before the Scythian bow, most bows had either straight hand grips or deflexed ones like the angular composite bow.

If the early Akkadian bows were of simple composite construction, they may have had a slight reflex-induced setback in the hand grip, but it is almost invisible in the artwork which is all that survives.

I am not a bowyer so I heavily rely on the insight of bowyers as well as looking at bows that I have access too. This might be why I have difficulty understanding the design of these Scythian style bows.